Re: [RFC v4 4/7] PCI: hv: Generify PCI probing

From: Bjorn Helgaas <helgaas@kernel.org>
To: Boqun Feng <boqun.feng@gmail.com>
Cc: "Bjorn Helgaas" <bhelgaas@google.com>,
	"Arnd Bergmann" <arnd@arndb.de>, "Marc Zyngier" <maz@kernel.org>,
	"Catalin Marinas" <catalin.marinas@arm.com>,
	"Will Deacon" <will@kernel.org>,
	"K. Y. Srinivasan" <kys@microsoft.com>,
	"Haiyang Zhang" <haiyangz@microsoft.com>,
	"Stephen Hemminger" <sthemmin@microsoft.com>,
	"Wei Liu" <wei.liu@kernel.org>,
	"Dexuan Cui" <decui@microsoft.com>,
	"Lorenzo Pieralisi" <lorenzo.pieralisi@arm.com>,
	"Rob Herring" <robh@kernel.org>,
	"Krzysztof Wilczyński" <kw@linux.com>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org,
	linux-pci@vger.kernel.org,
	"Sunil Muthuswamy" <sunilmut@microsoft.com>,
	"Mike Rapoport" <rppt@kernel.org>
Subject: Re: [RFC v4 4/7] PCI: hv: Generify PCI probing
Date: Wed, 14 Jul 2021 14:49:35 -0500	[thread overview]
Message-ID: <20210714194935.GA1870211@bjorn-Precision-5520> (raw)
In-Reply-To: <20210714102737.198432-5-boqun.feng@gmail.com>

On Wed, Jul 14, 2021 at 06:27:34PM +0800, Boqun Feng wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> In order to support ARM64 Hyper-V PCI, we need to set up the bridge at
> probing time because ARM64 is a PCI_DOMAIN_GENERIC arch and we don't
> have pci_config_window (ARM64 sysdata) for a PCI root bus on Hyper-V, so
> it's impossible to retrieve the information (e.g. PCI domains, irq
> domains) from bus sysdata on ARM64 after creation.
> 
> Originally in create_root_hv_pci_bus(), pci_create_root_bus() is used to
> create the root bus and the corresponding bridge based on x86 sysdata.
> Now we create a bridge first and then call pci_scan_root_bus_bridge(),
> which allows us to do the necessary set-ups for the bridge.

Also here and other patches in this series:

  s/irq/IRQ/
  s/msi/MSI/

in subject lines, commit logs, comments.